Merge remote-tracking branch 'spi/fix/spidev' into spi-linus

[cascardo/linux.git] / drivers / gpu / drm / msm / msm_gem.c

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 6cd4af4..85f3047 100644 (file)
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -196,11 +196,20 @@ int msm_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
        struct drm_gem_object *obj = vma->vm_private_data;
        struct drm_device *dev = obj->dev;
+       struct msm_drm_private *priv = dev->dev_private;
        struct page **pages;
        unsigned long pfn;
        pgoff_t pgoff;
        int ret;
 
+       /* This should only happen if userspace tries to pass a mmap'd
+        * but unfaulted gem bo vaddr into submit ioctl, triggering
+        * a page fault while struct_mutex is already held.  This is
+        * not a valid use-case so just bail.
+        */
+       if (priv->struct_mutex_task == current)
+               return VM_FAULT_SIGBUS;
+
        /* Make sure we don't parallel update on a fault, nor move or remove
         * something from beneath our feet
         */